JP-A-2002-337426 discloses an image forming apparatus which forms an image on a sheet equipped with a non-contact tag. The non-contact tag wirelessly transmits and receives a tag data and stores the tag data therein. This image forming apparatus includes a cassette which holds sheets equipped with the non-contact tags and another cassette which stacks sheets not equipped with the non-contact tags. When a given data includes tag data to be written into a non-contact tag, the cassette holding the sheets equipped with the non-contact tags is selected, and an image is formed on the sheet. Further, the tag data are written into the non-contact tag.
JP-A-2005-313551 discloses an image forming apparatus having a plurality of cassettes respectively holding sheets of different sizes. The image forming apparatus includes a reader which establishes communication with a non-contact tag provided in a sheet, before the sheet fed from any of the plurality of cassettes reaches a registration position. In accordance with a print mode data acquired from the non-contact tag provided in the sheet, a print mode, such as a fixing temperature optimum for sheet quality or sheet thickness, is set, to thus perform printing. This image forming apparatus is provided with a plurality of readers with different communication frequencies or a reader which establishes communication by switching communication frequencies, to thus enable communication with a non-contact tag of different frequency.